The invention relates to a multicoupling device for lines, especially hydraulic lines, with coupling units, which are provided in a number corresponding to the number of connections to be produced and which each have a plug and a socket that receives the plug, and with first and second coupling parts. Here, the plug is mounted on one of these coupling parts and the socket of a corresponding coupling unit is mounted on the other of these coupling parts, with the coupling units being embodied as self-locking snap couplings, whose sockets each have a locking collar that can be displaced in relation to the socket. The two coupling parts can be brought together by means of operating elements and can be pressed apart and fixed relative to each other in the coupling position. The locking collars of the corresponding coupling unit interact with a switch plate, which is common for all of the coupling units and which lies between the two coupling parts. The switch plate can be adjusted in relation to one coupling part in the closing or opening direction of the coupling units. The two coupling parts can be moved in relation to each other by at least one operating element mounted on the switch plate by engagement via at least one curved engagement slot and a pin formed on the other coupling part into a closed and open position and can be mutually locked in their closed position.
Such multicoupling devices for connecting and disconnecting several pairs of hydraulic lines are known. These multicoupling devices are used especially such that the individual hydraulic lines cannot be connected to each other incorrectly. For this purpose, the first and second coupling parts are embodied such that these coupling parts can be brought together in a way that the plugs and the sockets of the individual coupling units can be connected only when the two coupling parts are in alignment.
In order to fix the two coupling parts in the brought-together position, in which the plugs and the sockets of the individual coupling units are connected to each other, the known multicoupling devices have mechanical connecting elements between the first and the second coupling part. For example, a known multicoupling device uses a connecting link guide for this purpose. Here, one of the coupling parts has plates, which are connected to two sides of this coupling part by means of a swivel pin and which can be turned by a lever. Each of these plates has a curved slot beginning at the side edge of the plate. The distance of the slot from the swivel pin decreases along the course of the slot. On the other coupling part, there are two pegs spaced apart laterally. By bringing the two coupling parts together until the pegs lie in the beginning regions of the slots, and then through subsequent pivoting of the swiveling lever, the two coupling parts are brought into complete engagement of the corresponding plugs in the sockets relative to each other and locked in this position. The force exerted by the two coupling parts on the mechanical connecting elements in the closed state of the multicoupling device corresponds to the sum of the forces exerted by the individual coupling units due to the pressure of the hydraulic oil. Due to the limit on the forces that can be received by the mechanical connecting elements, the permissible pressures in the individual hydraulic lines are limited to a relatively low value.
Various structural configurations of such multicoupling devices are known, for example, from U.S. Pat. No. 5,316,347, U.S. Pat. No. 5,507,530, and U.S. Pat. No. 4,615,546. Furthermore, in another known configuration (U.S. Pat. No. 3,527,480), a displaceable locking collar is arranged on the socket, with this locking collar then being connected rigidly to a coupling part. However, during the insertion process into the socket, there is no special holder for the plug itself and thus exact alignment is not guaranteed.
Furthermore, a configuration has become known (EP-A-0390715), in which the plug, the socket, and a locking collar are each connected rigidly to a coupling part, which requires a rather complicated connecting link control in order to move these coupling parts in relation to each other and to mutually lock these parts against shifting at the end.
Furthermore, from WO 01/50057, a multicoupling device is known, in which the coupling units are embodied as self-locking snap couplings, whose sockets each have a locking collar displaceable in relation to the socket for opening the snap coupling. Here, the locking collar of the socket of a corresponding coupling unit is mounted on the first or second coupling part and the socket body can be displaced in the longitudinal direction in relation to this coupling part. The locking collar is surrounded by an attachment socket, which is fixed in the first or second coupling part, preferably screwed into this coupling part. The locking collar is thus covered from the outside and can be moved only when one of the two coupling parts moves to a point where disengaging is possible.